Publications by authors named "P A Whitson"

Low Earth Orbit (LEO) has emerged as a unique environment for evaluating altered stem cell properties in microgravity. LEO has become increasingly accessible for research and development due to progress in private spaceflight. Axiom Mission 2 (Ax-2) was launched as the second all-private astronaut mission to the International Space Station (ISS).

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Background: Existing research regarding design improvements to the operating room (OR) is scarce and emphasizes the compelling need to measure and test new design strategies and interventions.

Methods: We propose a conceptual framework for measuring and improving OR physical space design by outlining how two existing measurement schemes can be adapted for ORs. The structure, process, outcomes model described by Donabedian in 1966 is used to show how each of these three measurement approaches can be used to evaluate OR design.

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Polarizable colloids are expected to form crystalline equilibrium phases when exposed to a steady, uniform field. However, when colloids become localized this field-induced phase transition arrests and the suspension persists indefinitely as a kinetically trapped, percolated structure. We anneal such gels formed from magneto-rheological fluids by toggling the field strength at varied frequencies.

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Background: The transition to microgravity eliminates the hydrostatic gradients in the vascular system. The resulting fluid redistribution commonly manifests as facial edema, engorgement of the external neck veins, nasal congestion, and headache. This experiment examined the responses to modified Valsalva and Mueller maneuvers measured by cardiac and vascular ultrasound (ECHO) in a baseline steady state and under the influence of thigh occlusion cuffs available as a countermeasure device (Braslet cuffs).

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Purpose: Exposure to microgravity affects human physiology and results in changes in urinary chemical composition during and after spaceflight, favoring an increased risk of renal stones. We assessed the efficacy of potassium citrate to decrease the stone risk during and after spaceflight.

Materials And Methods: The study was done in 30 long duration spaceflight crew members to the space stations Mir and International Space Station.

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